The Horizon Order Parameter
نویسنده
چکیده
We construct a diffeormorphism invariant operator that is sensitive to how far we are from the black hole horizon. Its expectation value blows up on the horizon and it is small away from the horizon. Using this operator, we propose a non-standard effective action that, we argue, captures some of the relevant physics of quantum black holes, including the absence of the horizon at the full quantum level. With the help of a toy version of this effective action, we speculate on a possible connection between UV/IR mixing and the cosmological constant problem.
منابع مشابه
Evaluating the performance of concentration-number (C-N) fractal model for separation of soil horizon regarding vertical distribution and 3D models
This study aims to evaluate the efficiency of the concentration-number (C-N) fractal model for discrimination of soil horizon regarding the depth distribution profile. In this regard, soil parameters such as pH, organic carbon content, calcareous mineral content, electrical conductivity and available phosphorus of Ziarat forestland in Golestan Province, north of Iran, has been investigated. The...
متن کاملAnalysis of Applying Event-triggered Strategy on the Model Predictive Control
In this paper, the event-triggered strategy in the case of finite-horizon model predictive control (MPC) is studied and its advantages over the input to state stability (ISS) Lyapunov based triggering rule is discussed. In the MPC triggering rule, all the state trajectories in the receding horizon are considered to obtain the triggering rule. Clearly, the finite horizon MPC is sub-optimal with ...
متن کاملQuantum Thermodynamics of Black Hole Horizons
Exploiting results recently proved in a technical paper (and some of them are reviewed herein in the language of theoretical physicists) we focus on quantization of the metric of a black hole restricted to the Killing horizon with universal radius r0. The metric is represented in a suitable manner after imposing spherical symmetry and, after restriction to the Killing horizon, it is quantized e...
متن کاملBlack Hole Horizons and Thermodynamics: A Quantum Approach
We focus on quantization of the metric of a black hole restricted to the Killing horizon with universal radius r0. After imposing spherical symmetry and after restriction to the Killing horizon, the metric is quantized employing the chiral currents formalism. Two “components of the metric” are indeed quantized: The former behaves as an affine scalar field under changes of coordinates, the latte...
متن کاملHorizon Adaptation for Nonlinear Model Predictive Controllers with guaranteed Degree of Suboptimality
We propose adaptation strategies to modify the standard constrained model predictive controller scheme in order to guarantee a certain lower bound on the degree of suboptimality. Within this analysis, the length of the optimization horizon is the parameter we wish to adapt. We develop and prove several shortening and prolongation strategies which also allow for an effective implementation. More...
متن کاملReaction Wheel Parameter Identification and Control through Receding Horizon-Based Null Motion Excitation
A torque tracking and parameter identification scheme using a receding horizon optimization is developed for an over-actuated spacecraft Reaction Wheel Array (RWA). Additional actuator motion, constrained to the null-space of the array, is provided in order to enhance persistence of excitation. Therefore, the system parameters are learned without inducing large perturbations to the controllable...
متن کامل